The present invention relates generally to health monitoring apparatuses, and more specifically to a system for non-intrusively monitoring the health status of a subject.
A subject's health status is typically evaluated by reference to a plurality of vital signs, such as pulse and respiration rates, temperature, blood oxygen saturation, weight and body hydration. Additional considerations include observations as to subject appearance and movement. These latter factors are also indicative of the subject's mental health, e.g., cognitive ability. Other cues are the degree of animation, compliance with responsibilities such as self-medication, forgetfulness as to whereabouts or activities, and the like.
In traditional residential care facilities, these indices are measured and observed by caregivers. While measurements are generally recorded, a portion of the observations is retained only in the institution's memory. This fact is especially true in the case of cognitive health cues.
Retention of caregiving personnel serves the critical role of logically preserving of the meaning and functionality of health data. Interacting with a patient over a period of time, a caregiver learns a great deal about the habits and individual vital sign trends of that patient. The large volumes of observed data provide evidence to support the diagnostic requirements of residential care professionals. Raw data pertaining to a subject's health status functions to provide the context in which present parameter values can be assessed.
With caregiver turnover, this context is minimized or lost unless the observed information has been reduced to writing for the new personnel. Typically, a fraction of the total observed data is so recorded. Sub-clinical observations are frequently useful in assessing subject health status, especially cognitive abilities. These data include subject demeanor, alertness, regularity and subject mobility. The common denominator is that these characteristics change gradually. They are therefore less noticeable to new personnel, who have not observed the subject over time and are not familiar with these characteristics.
Short institutional memory produces a lengthening of the time before caregivers or other health professionals become cognizant of a slow decline in a subject's health status. The delay in appreciating a decline causes a corresponding delay in responding to health deterioration of the subject. As a result, the subject suffers a depression in the quality of health care received.
Bed sensors, similar to those described herein, are known (e.g., U.S. Pat. Nos. 5,640,145; 4,633,237; and 5,554,835. However, these prior art sensors heretofore have been used to detect presence or absence of a subject. As well, U.S. Pat. No. 5,235,319 discloses a capacitive bed sensor for differentiating subject movement in a bed from subject departure from the bed, to remove inappropriate departure alerts.